Elementary, my dear Watson | The McGill Tribune


Everything is made up of something. Books are made out of pages, which are made of paper, which is made of wood. All these items are composed of molecular complexes that decompose into tiny atoms. What differentiates these atoms from one another is the number of subatomic particles, protons, and neutrons that make them up. This is what makes the elements distinct from each other.

For a long time people did not know what it was about. This ignorance persisted until the proto-science of alchemy gave rise to almost four hundred years ago. The first chemists initially found random elements, labeling them and labeling them erroneously, until the invention of the Periodic Table of Elements.

"Truth be told, chemical knowledge at the time was very chaotic," wrote Joe Schwarcz, director of the McGill Office for Science and Society, in an e-mail to The McGill Tribune. "Students basically memorized what happened when the chemicals were combined. They learned, for example, that when a piece of sodium was thrown into the water, [while] a piece of aluminum does not. Nobody really knew why.

The organization of the elements remained unclear until Dmitri Mendeleev, a Siberian-born chemistry professor at the Main Pedagogical Institute in St. Petersburg, Russia, began to record the atomic weights, names and properties of the known elements on the cards. In 1868 he created the first prototype of the periodic table, placing the elements in horizontal lines in order of atomic weight and grouping elements of similar properties into columns.

"Then came the most daring attack of Mendeleev," Schwarcz wrote. "He predicted from holes in his periodic table that undiscovered elements must exist."

Each element has a different and exciting tale of discovery. Initially, elements were found exploring nature, diving into caves or into the ocean to find substances that no human had ever laid eyes on and then manually analyzing their properties in the laboratory. Today, scientists found it all natural elements and, therefore, began to investigate elements that can only be created artificially.

Scott Bohle, a professor of chemistry at McGill and the Canadian president of bioinorganic chemistry research, has developed the process of modern elemental discovery.

"We discovered the whole stable [elements]or we think we've discovered [them]Bohle said. "But it's much more controversial now […] because you have to demonstrate that you have […] a new element. "

Bohle explained that nature manufactures many elements in nuclear explosions via fusion of calcium, a process in which a calcium atom collides with a larger atom to create a larger new molecule, usually verified via mass spectrometry.

Unfortunately, the larger the size of the molecules, the less stable are their configurations: Some of the largest of the periodic table exist by mere thousandths of a second before it begins to decay, releasing protons and neutrons and thus changing its elemental composition.

To mark the enormous scientific impact of Mendeleev's creation, UNESCO named the International Year of the Periodic Table 2019 to celebrate its 150th anniversary. Although they are more than a century old, modern scientists still refer to it.

"I used to write the basic table in about 75 seconds, but now I'm out of practice," said David Harpp, a professor in the Department of Chemistry. "It's easy to do with an hour of effort and it's helpful for students, I believe, to define relationships. They "own" the table instead of having to look around.

Singing the table seems to be another popular way of learning it, with a number of different music published online, including celebrity appearances of Sheldon Cooper and to Laura Pavelka, a professor at the McGill Department of Chemistry.

"Our inorganic chemistry course instructor insisted that we memorize the first line of transition metals, which I am terrible at […], so I did a little melody to sing the list of 10 elements, "wrote Pavelka in an email Grandstand. "The joke is with me, because I still remember them in order!"

No matter the field, the periodic table of elements has revolutionized the way scientists think and organize the elements that make up our world.


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